MySQL下group_concat函数的SAS实现
MySQL下的字符串聚合函数group_concat是一个非常实用的字符串合并函数， sas下的宏实现， %macro group_concat(input, output, id, string, length); data &output (drop=string_old); set &input (rename=(&string=string_old)); by &id; retain &string; length &string $ &length; * set large enough to accommodate the maximum…